<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta http-equiv="X-UA-Compatible" content="ie=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0, minimum-scale=0.5, maximum-scale=2.0, user-scalable=yes" />  
  <title>Document</title>
  <style>
    body{
      background-image: url(img/bg-image.png);
    }
    .header{
      width:100%;
      padding-top:5.5rem;
      display: flex;
      flex-direction: column;
      align-items:center;
    }
    .header-portrait{
      width: 7rem;
      height: 7rem;
      display: inline-block;
      background-color:white;
      border-radius:50%;
      background: url(img/portrait.png) no-repeat -.35rem;
    }
    .header span{
      color: white;
      font-size:1.3rem;
      margin-top:1rem;
    }
    .register{
      width:18.75rem;
      margin: 4rem auto;
      display: flex;
      flex-direction: column;
    }
    .register input{
      padding-left: 2rem;
      height: 2.5rem;
      border-radius: 2rem;
      border: none;
    }
    .register button {
      margin-top: 5rem;
      height: 2.5rem;
      border-radius: 2rem;
      background: #2E8DDF;
      border: none;
      color: white;
      font-size: 1.1rem;
    }
  </style>
</head>
<body>
  <header class="header">
    <div class="header-portrait"></div>
    <span>用户登录</span>
  </header>

  <form action="" class="register" method="POST">
    <input type="text" placeholder="请输入用户名"><br>
    <input type="password" name="p" value="" placeholder="请输入密码">
    <button type="submit">登录</button>
  </form>
</body>
</html>